Content viewing method and mobile information terminal used for same

ABSTRACT

A content viewing method uses a viewing system including a content distribution server distributing contents, a mobile information terminal, and a viewing device reproducing a content. The mobile information terminal transmits user identification information and a user password to the content distribution server. The content distribution server authenticates the mobile information terminal based on the user identification information and the user password. The mobile information terminal transmits an account issue request requesting an account for reproducing a desired content to the content distribution server. The content distribution server issues the account based on the account issue request and transmits the account to the mobile information terminal. The mobile information terminal stores the account. The mobile information terminal transmits the account by short-range wireless communication. The viewing device stores the account received by short-range wireless communication. The viewing device reproduces the desired content using the stored account.

TECHNICAL FIELD

The present invention relates to a content distribution system thatdistributes contents to a viewing device connected to a network and acontent viewing system for viewing contents on the viewing device thatreceives a broadcast wave.

BACKGROUND ART

Heretofore, Digital Right Management (DRM) technology for controllingand limiting usage and a duplication of copyright so as to protectcopyright of contents has been used for contents distributed from acontent distribution server connected via the Internet and contentstransmitted by terrestrial broadcasting or from a broadcast satellite.For a mechanism of the DRM technology, a distributed or broadcast andencrypted content is decrypted, restored and reproduced using uniqueinformation to a viewing device that receives the content for anencryption key apart from the content.

Hereby, since another viewing device has no unique information fordecrypting and decoding a content even if the content which isdistributed or a broadcast of which is received is supplied to the otherviewing device, it has been impossible to decode the content, andviewing and it has been impossible to prevent duplication of thecontent. A method of decoding a content in only a viewing device by akey being unique information to the viewing device includes a method ofreproducing the content by collating the key and an identificationnumber (user ID) read in the viewing device of the viewing device, amethod of decrypting the encrypted content using the identificationnumber (the user ID) of the viewing device for an encryption key, and amethod of multiplexing ciphers such as a first separate key is extractedon the basis of information decrypted using the key of the viewingdevice, a second separate key is further extracted using the extractedfirst separate key, and the content encrypted using the second separatekey is decrypted.

Further, a content distribution system that enables to another viewingdevice and renting a content distributing the content utilizing theabovementioned mechanism of the DRM technology, protecting copyright isproposed. For one example, Patent Literature 1 discloses that as contentreproduction means of a content receiving device being a renterreproduces a content stored in content storage means on the basis ofrenting authentication information when the content receiving devicebeing the renter acquires and stores the same content as a content heldby a renter from a content distribution device, renting of the contentcan be freely made.

CITATION LIST Patent Literature

PTL 1: Japanese Paten Application Laid-Open No. 2007-140960

SUMMARY OF INVENTION Technical Problem

However, in Patent Literature 1, for example, it is not speciallyreferred that a user is located in a viewable range of a viewing-desiredviewing device and views a renting-desired content with simpleoperation, holding a portable and user-friendly mobile informationterminal as one example of an authenticated information transmittingdevice. In addition, when a user holding a mobile information terminalseparates from a viewing device for any reason, a rented content is keptin a reproduced state in the viewing device and Patent Literature 1 doesnot disclose a configuration that can cope with a state or a situationin which the user views the rented content such as the user misses therented content.

Moreover, Patent Literature 1 does not refer to a view of a contentbroadcast using a radio wave on another viewing-desired viewing device,protecting copyright of the content.

Then, it is desired that when a user holding a mobile informationterminal views a distributed or broadcast renting-desired content on aviewing device in the vicinity, a content distribution system and acontent viewing system which can respectively provide user-friendlyviewing environment are provided.

Solution to Problem

One aspect of the present invention is a content viewing method using aviewing system including a content distribution server that distributesa content, a mobile information terminal, and a viewing device thatreproduces the content. This method includes a first step in which themobile information terminal transmits user identification informationand a user password to the content distribution server, a second step inwhich the content distribution server authenticates the mobileinformation terminal on the basis of the received user identificationinformation and the received user password, a third step in which themobile information terminal transmits an account issue request forrequesting an account for reproducing a desired content to the contentdistribution server, a fourth step in which the content distributionserver issues the account on the basis of the received account issuerequest and transmits the issued account to the mobile informationterminal, a fifth step in which the mobile information terminal storesthe received account, a sixth step in which the mobile informationterminal transmits the stored account by short-range wirelesscommunication, a seventh step in which the viewing device stores theaccount received by short-range wireless communication, and an eighthstep in which the viewing device reproduces the desired content usingthe stored account.

Another aspect of the present invention is a mobile information terminalused for a content viewing method using a viewing system including acontent distribution server that distributes a content, the mobileinformation terminal, and the viewing device that reproduces thecontent. The mobile information terminal is provided with a controlunit, a memory unit, a first communication unit for communicating withthe content distribution server, a second communication unit shorter incommunication distance than the first communication unit forcommunicating with the viewing device, and an input unit. The memoryunit stores user identification information and a user password. Thecontrol unit instructs the first communication unit to transmit the useridentification information and the user password to the contentdistribution server. In addition, the control unit instructs the firstcommunication unit to transmit an account issue request for requestingan account for reproducing a desired content to the content distributionserver and instructs the first communication unit to store the accountreceived from the content distribution server in the memory unit.Moreover, the control unit instructs the second communication unit tocontinuously or periodically transmit the account.

Advantageous Effects of Invention

When a user holding the mobile information terminal views a distributedor broadcast renting-desired content on the viewing device in thevicinity of the user, user-friendly viewing environment is acquired. Aproblem, a configuration and effect except the abovementioned ones willbe clarified according to description of the following embodiments.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing an example of a configuration of acontent distribution system.

FIG. 2A shows a former half of an example of an operational sequence ofthe content distribution system shown in FIG. 1 .

FIG. 2B shows a latter half of the example of the operational sequenceof the content distribution system shown in FIG. 1 .

FIG. 3 illustrates an operation processing example of an operation inputunit in the content distribution system shown in FIG. 1 .

FIG. 4 illustrates an operational example of the content distributionsystem.

FIG. 5 shows an example of another operational sequence of the contentdistribution system shown in FIG. 1 .

FIG. 6 is a block diagram showing an example of a configuration of acontent viewing system.

FIG. 7A shows a former half of the example of the operational sequenceof the content viewing system shown in FIG. 6 .

FIG. 7B shows a latter half of the example of the operational sequenceof the content viewing system shown in FIG. 6 .

FIG. 8 is a block diagram showing an example of another configuration ofthe content viewing system.

FIG. 9A shows a former half of an example of an operational sequence ofthe content viewing system shown in FIG. 8 .

FIG. 9B shows a latter half of the example of the operational sequenceof the content viewing system shown in FIG. 6 .

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described referring to thedrawings below. In the following configurations of the presentinvention, the same reference numeral is used for the same part or apart having the similar function in common among different figures andduplicate description may be omitted.

Description of “first”, “second”, “third”, and the like in thisspecification is allocated to identify components and a number, order orcontents are not necessarily limited. In addition, a reference numeralfor identifying a component is used for every context and a referencenumeral used in one context does not necessarily denote the sameconfiguration in another context. Moreover, a component identified by acertain reference numeral is prevented from also having a function of acomponent identified by another reference numeral.

A summary of technique described in the embodiments will be firstexplained. One of the embodiments relates to a content distributionsystem in which a content distribution server, a mobile informationterminal, and a viewing device are connected via a network. The mobileinformation terminal transmits user identification information and auser password to the content distribution server and the contentdistribution server authenticates the mobile information terminal on thebasis of the received user identification information and the receiveduser password. The mobile information terminal transmits contentidentification information for identifying a viewing-desired contentprogram and an account issue request to the content distribution server,the content distribution server issues an account including the contentidentification information on the basis of the received contentidentification information and the received account issue request, andthe content distribution server transmits the issued account to themobile information terminal. The mobile information terminal transmitsthe received account to the viewing device by short-range wirelesscommunication, the viewing device transmits a content program viewingrequest to the content distribution server together with the receivedaccount, and the content distribution server distributes the contentprogram to the viewing device on the basis of the account for theviewing request. The viewing device a member of the content distributionsystem having a characteristic that the viewing device enables viewingof the distributed content program. In addition, in an appliedembodiment of this system, a mobile information terminal continuouslytransmits an account by short-range wireless communication and a viewingdevice interrupts viewing of the content when reception of the accounttransmitted from the mobile information terminal is interrupted.

Another embodiment relates to a content viewing system configured bybroadcast-side equipment provided with a content program distributionserver, a mobile information terminal, and a viewing device. The mobileinformation terminal transmits user identification information and auser password to the content distribution server and the contentdistribution server authenticates the mobile information terminal on thebasis of the received user identification information and the receiveduser password. The mobile information terminal transmits aviewing-desired broadcast content program or content identificationinformation for identifying a broadcast channel and an account issuerequest to the content distribution server, the content distributionserver issues an account including key information required fordecrypting the broadcast content program or the broadcast channel on thebasis of the received content identification information and thereceived account issue request, and the content distribution servertransmits the issued account to the mobile information terminal. Themobile information terminal transmits the received account to theviewing device by short-range wireless communication and thebroadcast-side equipment transmits the broadcast content program or thebroadcast channel and encrypted related information including ascrambling key for decrypting the broadcast content program or thebroadcast channel. The viewing device decrypts the related informationby key information included in the account received from the mobileinformation terminal, decrypts the broadcast content program or thebroadcast channel using the scrambling key extracted by decrypting therelated information, and enables viewing of the broadcast contentprogram or the broadcast channel.

The abovementioned content program is not necessarily required to be aunit of one program and may also be one channel unit or one category ora unit of a group. According to the technique described in theembodiments, a user can acquire an account for viewing on the mobileinformation terminal and transplants the account to a viewing deviceprovided with a function that outputs images and audio if necessary soas to enable viewing of a content on the viewing device. In addition,the mobile information terminal and the viewing device detect that theyexist in close positions owing to continuous reception verification ofan account and can control interruption and resumption of reproducingthe content. In this case, “continuous” is a concept including bothcontinuous reception on the receive side and reception at apredetermined cycle. Moreover, the transmit side may also perform eitherof continuous transmission or transmission at a predetermined cycle. Thedetails will be described below.

Example 1 1. Whole Configuration

FIG. 1 is a block diagram showing one example of a content distributionsystem according to this embodiment. The example shown in FIG. 1 isconfigured suitably using a mobile information terminal 10, a contentdistribution server 20, a viewing device 30, a base station 40, and anexternal network 50.

The mobile information terminal 10 communicates with the base station 40by wireless telecommunication such as Wideband Code Division MultipleAccess (W-CDMA) and Global System for Mobile communications (GSM)(trademark) and transmits user identification information 102 a and auser password 102 b respectively set and stored in the mobileinformation terminal 10 to the content distribution server 20 via theexternal network 50.

The content distribution server 20 collates the user identificationinformation 102 a, the user password 102 b respectively received anduser identification information 206 a, a user password 206 brespectively registered as a user beforehand, and authenticates themobile information terminal 10 as a user. In addition, the contentdistribution server 20 issues an account including identificationinformation of the already registered rental viewed content program(s)by a fee-based contract, and the like and being information that enablesrental on the basis of a user authentication result, and transmits it tothe mobile information terminal 10.

The mobile information terminal 10 transmits the received account to theviewing device 30 by short-range wireless communication such as an RFIDtag. In this case, when a user holding the mobile information terminal10 approaches a viewable range in the viewing device 30 desired by theuser, the viewing device 30 receives the account. In addition, theviewing device 30 transmits the received account to the contentdistribution server 20 via the external network 50 and receives a rentalcontent program desired by the user from the content distribution server20.

Next, each configuration of the mobile information terminal 10, thecontent distribution server 20, and the viewing device 30 will bedescribed.

2. Configuration of Mobile Information Terminal

The mobile information terminal 10 is configured suitably using acontrol unit 101, a memory unit 102, a base station communication unit103, an audio input-output processing unit 104 including a microphoneand a speaker, a short-range wireless communication unit 105, anoperation input unit 106, and a display 107, and each component ismutually connected via a bills 100.

The control unit 101 is configured by a central processing unit (CPU),and the like and controls each component so as to execute variousprocessing by executing a program stored in the memory unit 102. Thememory unit 102 is a flash memory, and the like, and stores variousprograms used by the control unit 101 and data such as the useridentification information 102 a and the user password 102 b eachsetting of which is input in the operation input unit 106, contentidentification information 102 c and further, an account 102 d receivedfrom the content distribution server 20.

The base station communication unit 103 is a communication interfacethat executes wireless telecommunication with the base station 40 suchas W-CDMA and GSM. Hereby, the base station communication unit connectswith the external network 50 via the base station 40 andtransmits/receives information such as the user identificationinformation 102 a, the user password 102 b, the content identificationinformation 102 c and the account 102 d.

The operation input unit 106 is an electrostatic capacitance touchpadtype input means for example and detects approach or contact operation(hereinafter called a touch) by a finger, a touch pen, and the like asoperational input. A user in possession of the mobile informationterminal 10 can input and set the user identification information 102 aand the user password 102 b via the operation input unit 106 so as toacquire authentication that the mobile information terminal 10 isalready registered in the content distribution server 20 as a user. Inaddition, the user can set a rental content program which the userdesires to view according to menu selection, and the like. The display107 displays video and images on a liquid crystal panel, and the likeand is provided with the operation input unit 106 on its display screen.

The audio input-output processing unit 104 includes a microphone thatinputs external audio and a speaker that outputs audio outside, andexecutes processing of input-output audio.

The short-range wireless communication unit 105 transmits/receivesinformation data to/from the viewing device 30 in a range in whichshort-range wireless communication is possible by short-range wirelesscommunication under control by the control unit 101. That is, theshort-range wireless communication unit transmits the account 102 dincluding content identification information transmitted from the mobileinformation terminal 10 to the viewing device 30.

The short-range wireless communication unit 105 communicates using anelectronic tag in this embodiment. However, the present invention is notlimited to this, and if only communication by wire is enabled when themobile information terminal 10 is located close to the viewing device30, short-range wireless communication may also be made using Bluetooth(trademark), Infrared Data. Association (IrDA), Zigbee (trademark), HomeRadio Frequency (HomeRF) (trademark) or wireless LAN (IEEE802.11a,IEEE802.11b, IEEE802.11 g). A short range in this embodiment meansdistance between a user and a viewing device in viewing contents and isa concept contrastive with a communication system for a mobile phone,and the like. For example, the short range means distance ofapproximately 20 m or less.

3. Configuration of Content Distribution Server

The content distribution server 20 is configured suitably using acontrol unit 201, a memory unit 202, a communication unit 203 and astorage 204, and respective units are mutually connected via a bus 200.

The control unit 201 is configured by CPU, and the like and controlseach component so as to execute various processing by executing aprogram stored in the memory unit 202.

The communication unit 203 is an interface for connecting to theexternal network 50, receives the user identification information 102 a,the user password 102 b and the content identification information 102 cfrom the mobile information terminal 10 corresponding to networkconnection via the base station 40, and transmits the account 206 cissued by the content distribution server 20 to the mobile informationterminal 10. In addition, the communication unit 203 receives an account302 a from the viewing device 30 via the external network 50 andtransmits a content program stored in a content information storage area205 in the storage 204 to the viewing device 30.

The storage 204 is provided with the content information storage area205 that stores content programs themselves, content identificationinformation, as well as content accompanying information such as whetherthe content program is charged or not, and the like and a userinformation storage area 206 that stores the user identificationinformation 206 a and the user password 206 b respectively registered asa user beforehand, the account 206 c newly issued, and the like.

The content distribution server 20 collates the user identificationinformation 102 a and the user password 102 b respectively from themobile information terminal 10 and the registered user identificationinformation 206 a, the registered user password 206 b in theabovementioned configuration. When they are coincident, the contentdistribution server authenticates the mobile information terminal 10 asa mobile user, issues the account 206 c that enables distribution of aviewing-desired content program, records the account in the userinformation storage area 206, and transmits it to the mobile informationterminal 10 via the communication unit 203.

In the meantime, the content distribution server 20 extracts the contentprogram based upon content identification information included in theaccount 302 a from the content information storage area 205 when thecontent distribution server receives the account 302 a from the viewingdevice 30 via the communication unit 203, and distributes the contentprogram to the viewing device 30 via the communication unit 203 and theexternal network 50.

4. Configuration of Viewing Device

The viewing device 30 is configured control unit 301, a memory unit 302,a storage unit 303, a short-range wireless communication unit 304, adisplay 305, a communication unit 306, and an operation input unit 307.

The control unit 301 is configured by CPU, and the like, and controlsthe whole viewing device 30 according to an operating system, variousapplication programs, and the like respectively stored in the memoryunit 302 .

In addition, the memory unit 302 stores the account 302 a received bythe short-range wireless communication unit 304. A bus 300 is a datatransmission channel for data transmission/reception between the controlunit 301 and each component in the viewing device 30.

The storage unit 303 stores the content program received from contentdistribution server 20. In addition, the communication unit 306transmits and receives data to/from the external network 50 such as theInternet by wired LAN or wireless LAN and downloads the content programfrom the content distribution server 20 via the external network 50. Atthis time, the downloaded content is stored in a content recording area303 a in the storage unit 303.

The operation input unit 307 is an instruction input unit for inputtingan operational instruction to the viewing device 30 and in thisembodiment, is suitably configured using operation keys such as a bottomswitch.

The display 305 is a display device such as a liquid crystal panel anddisplays the content program received via the communication unit 306 orthe content program stored in the storage unit 303. When the contentprogram is read from the storage unit 303 and is viewed, the contentprogram can be viewed without causing temporary interruption of viewingby retarding reading from the storage unit 303 by time enough todissolve interruption and delay of content distribution even if thetemporary interruption and delay of content distribution are causedbecause of congestion of the external network 50, and the like indistributing content data in the external network 50.

Owing to the abovementioned configuration, the user registered in thecontent distribution server beforehand can view the viewing-desiredcontent program rental from the content distribution server on thefreely selected viewing device located close to the user anywhere and onany viewing device using the mobile information terminal in possessionof the user, and usable content program viewing environment can beacquired.

5. Operation of Content Distribution System

Next, an operational example of the content distribution system will bedescribed.

FIGS. 2A and 2B show one example of an operational sequence of thecontent distribution system shown in FIG. 1 . First, as shown in FIG.2A, a user makes a request for a rental viewing-desired content programusing a button, a menu screen, and the like of the operation input unit106 on the mobile information terminal 10 (S201). A unit of rentalcontents is arbitrary in units of a channel and a program.

Hereby, the mobile information terminal 10 accesses the contentdistribution server 20 from the base station communication unit 103 viathe base station 40 and the external network 50, requests and acquireslog-in screen information (S202).

The mobile information terminal 10 displays a log-in screen on thedisplay 107 and the user inputs user identification information 102 aand a user password 102 b as log-in information via the operation inputunit 106 (S203).

The mobile information terminal 10 transmits the user identificationinformation 102 a and the user password 102 b respectively input andstored to the content distribution server 20 via the external network 50(S204).

The content distribution server 20 collates the user identificationinformation 206 a, the user password 206 b respectively stored in theuser information storage area 206 in the storage 204 as user informationregistered as a charged contract, and the like and the useridentification information 102 a, the user password 102 b respectivelytransmitted from the mobile information terminal 10, authenticates thatthe user in possession of the mobile information terminal 10 is a normalregistered user (S205), and transmits a user authentication result tothe mobile information terminal 10 (S206).

The user inputs a viewing-desired content program via the operationinput unit 106 after the user verifies reception of the userauthentication result from the content distribution server 20 on themobile information terminal 10, and stores the input content program inthe memory unit 102 as content identification information 102 c (S207).Afterward, the mobile information terminal 10 transmits the inputcontent identification information to the content distribution server 20via the base station communication unit 103 and the external network 50and requests issue of an account (S208) . When the viewing-desiredcontent program is uniquely specified at the time of the content rentingrequest (S201), the input of the viewing-desired content program (S207)may also be omitted.

The content distribution server 20 receives a request for issuingcontent identification information and the account, issues the accountincluding the content identification information after the contentdistribution server verifies that viewing of a content programcorresponding to the content identification information is registered,and further, stores the issued account in the user information storagearea 206 for example of the storage 204 as the account 206 c (S209).

In addition, the content distribution server 20 transmits the issuedaccount to the mobile information terminal 10 via the external network50 and the base station 40 (S210). The mobile information terminal 10stores the received account in the memory unit 102 as an account 102 d(S211 a).

According to the abovementioned account generation process, the contentdistribution server 20 authenticates the user using the useridentification information and the user password respectively input andset on the mobile information terminal 10, issues the account as aresult of authenticating renting for viewing the viewing-desired contentprogram set on the mobile information terminal 10, and the mobileinformation terminal 10 can receive and store the account transmittedfrom the content distribution server 20 (S200 a). However, order of thesteps S201, S203, S207 executed by the mobile information terminal 10 isnot limited to the order shown in FIG. 2A, the order may also bechanged, and the steps may also be simultaneously executed.

Next, as shown in FIG. 2B, when the user closely holding the mobileinformation terminal 10 approaches the viewing-desired viewing device 30for example and the user performs simple one-touch input operation onthe operation input unit 106, the mobile information terminal 10 startstransmission of an account 102 d by short-range wireless communicationin the short-range wireless communication 105 (S211 b). The transmittedaccount 102 d is transmitted to the viewing device 30 existing in thevicinity of the mobile information terminal (S212). As for the mobileinformation terminal 10, operation such as start, continuation,interruption and resumption of transmission of an account may also beenabled.

When plural viewing devices exist in the vicinity of the mobileinformation terminal, only the viewing-desired viewing device has to bemade in a waiting state for reception of the account by operation inadvance of the user. For example, only the viewing-desired viewingdevice 30 can be made in a waiting state for reception of the account byinputting and setting to/in the viewing-desired viewing device 30 usingthe operation input unit 307 so that the short-range wirelesscommunication unit 304 is ready to receive the account. The viewingdevice 30 periodically performs processing for discriminating whetherthe account 102 d transmitted from the mobile information terminal byshort-range wireless communication exists in a receivable close rangeand can be received or whether the account 102 d exists outside thereceivable vicinity and cannot be received at a certain interval (S213).The period may also be set to every 10 seconds to 30 minutes forexample. However, the user may also arbitrarily select in apredetermined range.

When the viewing device 30 can receive the account 102 d, the viewingdevice 30 transmits an account 302 a received and stored from the mobileinformation terminal and stored and viewing device ID for specifying theviewing device 30 to the content distribution server 20 from thecommunication unit 306 via the external network 50, and requests viewingof the desired rental content program (S214).

When the content distribution server 20 collates the received account302 a and the issued account 206 c stored in the storage 204 andverifies that they are coincident, the content distribution server readsthe content program fitted to viewing-desired content identificationinformation included in the received account 302 a from the contentinformation storage area 205 and enables the content program to bedistributed (S215), and transmits the distributable content program tothe viewing device 30 specified on the basis of the viewing device ID(S216).

In the viewing device 30, the content program distributed from thecontent distribution server 20 can be viewed via the display 305 and thespeaker 309 (S217). In addition, it is discriminated whether thedistributed content program is finished or not (S218) and whendistribution of the content program to the viewing device is notfinished, the abovementioned periodic verification of account receptionis repeated (S219). The viewing device 30 can verify that a user havinga suitable authorization of viewing is located in short distance, thatis, in a viewable range by continuing monitoring of an account byshort-range wireless communication.

When distribution of the content program to the viewing device isfinished, viewing the program is finished (S220) and information showingan end of the viewing program is transmitted to the mobile informationterminal 10 from the viewing device 30 (S221). At this time, the viewingdevice 30 deletes the account 302 a stored in the memory unit 302 initself. The mobile information terminal 10 receives the end of viewingthe content program, stops transmission of the account 102 d to theviewing device 30 (S222), and terminates the content viewing on theviewing device by renting the account.

In the meantime, when the viewing device 30 cannot receive the account102 d from the mobile information terminal 10, the viewing device 30stops the request for viewing the renting-desired content program to thecontent distribution server 20 from the communication unit 306 via theexternal network 50 (S223). The content distribution server 20 receivesthe stop of the request for viewing the content program and executesprocessing for stopping distribution of the content program (S224). Theviewing device 30 interrupts providing the content program (S226)according to the stop of transmitting the content program (S225) andreturns to processing for repeating the periodic verification ofreceiving an account (S227).

When the viewing device 30 receives an account again during the periodicverification of receiving an account (S213), the viewing device requestsviewing of a renting-desired content program again (S214). Hereby,distribution of the program is resumed. However, when predeterminedtime, for example one hour, elapses since the last account reception,the viewing device judges that the user does not return any longer anddeletes the account 302 a stored in the memory unit 302 in itself.Processing for deleting the account 302 a in the viewing device 30 isalso similar in another embodiment.

According to the content viewing process by the abovementionedtransmission/reception of the account, the viewing devicestarts/continues/interrupts/resumes viewing of the viewing-desiredcontent program distributed from the content distribution serveraccording to a result of the periodic verification of receiving anaccount from the mobile information terminal (S200 b).

Consequently, there is produced effect that when the user closelyholding the mobile information terminal 10 exists in the vicinity of theviewing device 30, the user transmits the account by short-rangewireless communication by the simple one-touch input operation on themobile information terminal and the viewing device 30 can receive theaccount from the mobile information terminal by short-range wirelesscommunication, the user can view the renting/viewing-desired contentprogram distributed from the content distribution server on a viewingdevice close to the user anywhere.

In addition, when the user holding the mobile information terminalseparates from the viewing device, the viewing device identifies thatthe user separates because reception of the account is impossible, stopsdistribution of the content, and can temporarily interrupt (pause)viewing of the distributed content program on its screen. Afterward,when the user holding the mobile information terminal approaches thevicinity of the viewing device again, the viewing device can resume theviewing of the content program because the reception of the account isturned possible, and therefore, the user can acquire effect that thestart/the continuation/the resumption of viewing the content program areusably enabled by the simple one-touch operation.

When the user temporarily separates from the viewing device withouthaving the mobile information terminal and interrupts viewing thecontent program halfway even if the viewing device is located in a closerange that enables receiving the account from the mobile informationterminal, the user inputs and sets interruption of viewing via theoperation input unit 106 and may also stop transmission of the account102 d from the short-range wireless communication unit 105. Further,when the user returns to the vicinity of the viewing device, the userinputs and sets resumption of viewing via the operation input unit 106of the mobile information terminal and has only to resume transmissionof the account 102 d from the short-range wireless communication unit105. In this case, usable usage environment can also be realized for auser not holding a mobile information terminal by setting theinterruption and the resumption of viewing the content program byhimself/herself in addition to control over viewing a content programdepending upon transmission/reception of the account from the mobileinformation terminal.

6. Operational Screen Example of Mobile Information Terminal

FIG. 3 shows a screen display example in operation on the operationinput unit 106 of the mobile information terminal 10. A display screen106 a is a display screen example when a request for renting aviewing-desired content is made to the content distribution server 20 byselecting the renting request using a functional menu, and the like ofthe mobile information terminal 10 and clicking a displayed START button(S201). Hereby, log-in screen information can be requested and acquired(S202).

Display screens 106 b, 106 c are display screen examples when useridentification information (ID) and a user password are next inputaccording to an operation input menu of the mobile information terminal10 on the basis of acquisition of the log-in screen informationtransmitted from the content distribution server 20.

A display screen 106 d is a display screen example when aviewing-desired content program is selected and set on the mobileinformation terminal 10 after the content distribution server 20collates the user identification information and the user password,authenticates the user and the mobile information terminal 10 receivesan authentication result. The display screen is the example in a casewhere a category such as a movie and a drama of contents is selected andfurther, a viewing-desired content program is selected and set in adetailed menu (not shown). However, the present invention is not limitedto this, and a viewing-desired content program has only to be selectedand set by inputting a viewing-desired content program name for example.In addition, the registered user may also make the content programs theviewing of which is contracted beforehand displayed and may also selectout of them.

A display screen 106 e is a display screen example showing that themobile information terminal 10 receives an account including contentidentification information issued by the content distribution server 20to the user by display of RECEIVED. Hereby, the user closely holding themobile information terminal 10 can recognize that transmission of theaccount to the viewing device 30 is enabled.

A display screen 106 f is a display screen in a case where the accountis transmitted to the viewing device 30 when the user in the vicinity ofthe viewing device 30 for the user closely holding the mobileinformation terminal 10 to view the viewing-desired content programclicks a displayed START button after RECEIVED is displayed on thedisplay screen 106 e. Hereby, the account can be transmitted to theviewing device 30 from the mobile information terminal 10 by one-touchoperation and when the viewing device 30 can receive the account, theviewing-desired content program can be viewed on the viewing device 30.In addition, when the user closely holding the mobile informationterminal 10 separates from the viewing device 30 and the viewing device30 cannot receive the account, viewing of the content program can beinterrupted (paused) at that time, and when the user approaches theviewing device 30 again afterward and the viewing device can receive theaccount, viewing of the content program can be resumed. Moreover, in acase where the user once separates from the viewing device withouthaving the mobile information terminal and once interrupts the viewingof the content program on the viewing device, interruption of viewing isenabled when the user clicks a STOP button on the display screen 106 feven if the mobile information terminal is located in the vicinity ofthe viewing device. Hereby, transmission/reception of the accountto/from the viewing device 30 on the mobile information terminal 10 inthe vicinity of the viewing device can be controlled by one-touchoperation and while the account can be received, the viewing-desiredcontent program can be viewed on the viewing device 30.

In the one-touch transmission (S211 b) of the account by short-rangewireless communication, transmission by the mobile information terminal10 can be made intermittent by periodically transmitting perpredetermined time in synchronization with periodic receptionverification timing in the viewing device 30, and effect that powerconsumption of the mobile information terminal can be greatly reduced isacquired.

7. Example of Relay Viewing

Next, a case where viewing is interrupted in a certain viewing device 30and is continued relaying the viewing to another viewing device will bedescribed.

FIG. 4 shows an example explaining operation for relay viewing in whichviewing of a content program is started in a viewing device 31 havingthe similar configuration to that of the viewing device 30, the viewingin the viewing device 31 is interrupted (paused) during rental viewing,a user moves to another viewing device 32 having the similarconfiguration to that of the viewing device 30 holding the mobileinformation terminal 10, the user repeats interruption/resumption ofviewing the content program by performing rental viewing operation andthe user views the content program, relaying the content program betweenthe plural viewing devices.

As shown in FIG. 4 , (a) shows an image when a user starts to view thecontent program on the viewing device 31 using the mobile informationterminal 10 in a home A provided with the viewing device 31, afterward,the user moves to a home B provided with the viewing device 32 andfurther, the user resumes viewing the content program on the viewingdevice 32. (b) shows a position of the user holding the mobileinformation terminal 10. (c) shows a state of transmission/reception ofan account from the mobile information terminal to the viewing device.It is an account from the mobile information terminal to the viewingdevice, an interruption flag or an interruption position pointer thatare transmitted/received. (d) shows a state of reviewing of the contentprogram.

As shown in (a), (b), the user approaches the viewing device 31 in thehome A, performs an account generation process (S200 a), and further,performs one-touch transmission operation (S211 b) of the account byshort-range wireless communication. Hereby, when thetransmission/reception of the account is made between the mobileinformation terminal 10 and the viewing device 31 as shown in (c), thecontent program can be viewed on the viewing device 31 in the home A asshown in (d) . These processing is similar to the processes S200 a, S200b shown in FIGS. 2A, 2B.

Afterward, when the user moves from the home A to the home B, holdingthe mobile information terminal 10, a moving course is outside atransmission/reception range of the account (S240) as shown in (b) , (c), (d) , the transmission/reception between the mobile informationterminal 10 and the viewing device 31 of the account is turnedimpossible, and viewing of the content program is interrupted. Or theviewing of the content program is similarly interrupted by stoppingtransmission of the account (S240) by operation of the STOP button onthe display screen 106 f of the mobile information terminal 10.

In addition, the viewing device 31 transmits a viewing interruptionposition of the content program, an interruption flag showing viewinginterruption time or an interruption pointer to the mobile informationterminal 10 when the viewing is interrupted and the mobile informationterminal 10 stores the received interruption flag or the receivedinterruption pointer in the memory unit 102. Viewing positioninformation showing a viewing position of the content program iscontinuously transmitted/received between the mobile informationterminal 10 and the viewing device 31 and when viewing is interrupted,the viewing position information may also be stored in the memory unit102 as the interruption flag or the interruption pointer.

Further, as shown in (a), (b), when the user moves to the home B,approaches the viewing device 32 and enters the transmission/receptionrange of the account (S241), the transmission/reception of the accountis made again between the mobile information terminal 10 and the viewingdevice 32 and the viewing of the content program can be resumed on theviewing device 32 in the home B as shown in (c) , (d) . Or after theuser approaches the viewing device 32 in the home B and enters thetransmission/reception range of the account, the viewing of the contentprogram can be similarly resumed by resuming the transmission of theaccount once stopped by operating the START button on the display screen106 f of the mobile information terminal 10 (S241). In S241 being theprocessing when the viewing is resumed, as the user already storesinformation of the account in the mobile information terminal 10, theprocess S200 a shown in FIG. 2A is not required and S241 is basicallysimilar to the process S200 b shown in FIG. 2B. However, as the viewingis resumed on the way of the content program, the following processingis included.

The mobile information terminal 10 transmits the interruption flag orthe interruption pointer respectively stored in the memory unit 102 ofthe mobile information terminal 10 to the viewing device 32 and theviewing device 32 resumes the reception of the content program from thecontent distribution server 20 from the viewing interruption position onthe basis of the received interruption flag or the received interruptionpointer. At this time, when the interruption flag or the interruptionpointer is stored in the memory unit 102, the mobile informationterminal 10 may also continuously transmit the account to which theinterruption flag or the interruption pointer is added. Or theinterruption flag or the interruption pointer is added separately fromthe account and may also be continuously transmitted. Or, though thefollowing timing is not shown, the interruption flag or the interruptionpointer may also be transmitted at timing at which the mobileinformation terminal 10 receives a response from the viewing device 32that verifies reception of the account.

Therefore, the viewing devices are taken over by transmitting/receivingthe account, the interruption flag or the interruption pointerrespectively from the mobile information terminal to the viewing deviceby the simple one-touch operation using the mobile information terminaland relay viewing of the content program can be realized until theviewing of the content program is finished.

For an example when no interruption flag or no interruption pointer isused, relay viewing of the content program may also be consecutivelymade on another viewing device by storing an interupted position of theviewing-interrupted program in the storage 204 of the contentdistribution server 20 when transmission of the content program from thecontent distribution server 20 to the viewing device 31 is interruptedand afterward, resuming the distribution on the other viewing devicefrom the interrupted position of the program stored in the storage 204according to a request from the other viewing device 32 for resuming theviewing of the content program the viewing of which is interrupted.

Example 2

FIG. 5 shows another example of an operational sequence of the contentdistribution system shown in FIG. 1 . As in FIG. 5 , each sequentialpart which is shown in FIGS. 2(a), 2(b) and to which the same referencenumeral is allocated has the same operation as the operation alreadydescribed referring to FIGS. 2(a), 2(b), detailed description of them isomitted.

In FIG. 5 , an account generation process (S200 a), one-touchtransmission operation of an account by short-range wirelesscommunication (S211 b), and transmission of the transmitted account to aviewing device 30 (S212) are as described referring to FIGS. 2(a), 2(b).A mobile information terminal 10 transmits an account 102 d to theviewing device 30 by one-touch click operation on the mobile informationterminal 10 of a user.

The viewing device 30 periodically verifies reception of the account 102d at a certain fixed interval (S213 a). The periodic verification ofreception is continued until the viewing device 30 receives the account102 d transmitted from the mobile information terminal 10 by short-rangewireless communication by approach of the mobile information terminal 10to the viewing device 30 (S213 a).

When the viewing device 30 can once receive the account 102 d, theviewing device 30 transmits the received and stored account 302 a to acontent distribution server 20 from a communication unit 306 via anexternal network 50 and requests viewing of a renting-desired contentprogram (S214) .

The content distribution server 20 collates the received account 302 aand an issued account 206 c stored in a storage 204, enables reading acontent program fitted to viewing-desired content identificationinformation included in. the received account from a content informationstorage area 205 and distributing the content program (S215 a,) when theaccounts are coincident, and transmits the content program to theviewing device 30 to an end of the program (S216).

On the viewing device 30, the content program distributed from thecontent distribution server 20 is viewed via a display 305 and a speaker309 (S217 a). In addition, the viewing device 30 continues viewing ofthe content program until distribution of the content program to theviewing device is finished by discriminating processing (S218) ofwhether the distributed content program is finished or not (S219 a), andterminates the viewing of the program together with an end of thedistribution of the content program to the viewing device (S220).

After the viewing of the content program is finished, the viewing device30 transmits information showing the end of the viewing program to themobile information terminal 10 (S221), the mobile information terminal10 receives the end of the viewing of the content program, and stops thetransmission of the account to the viewing device 30 (S222) . Theviewing device periodically verifies the reception of the account fromthe mobile information terminal, by the abovementioned content viewingprocess by the transmission/reception of the account and when theviewing device receives the account, the viewing device enables a userto view the viewing-desired content program distributed from the contentdistribution server (S200 c) .

Even if a person except the user goes out with the mobile informationterminal 10 for example after the user closely holds the mobileinformation terminal 10 and starts to view a content program in thevicinity of the viewing device 30, the mobile information terminal 10 isseparated from the viewing device 30 and the viewing device 30 cannotreceive the account 102 d from the mobile information terminal 10, theuser can view the content program to the end.

Example 3

Next, an example not in a case where a registered content programtransmitted from a content distribution server via an external networkis rented and viewed but in a case where a registered content programbroadcast using a radio wave according to a. fee-based contract isviewed on a viewing device in the vicinity of a mobile informationterminal will be described.

FIG. 6 is a block diagram showing one embodiment of a content viewingsystem according to this embodiment. To explain the difference from theconfiguration shown in FIG. 1 , the mobile information terminal 10 shownin FIG. 1 is replaced with a mobile information terminal 11 in FIG. 6 ,the mobile information terminal 11 stores broadcast contentidentification information 102 e in place of the content identificationinformation 102 c, and the mobile information terminal 11 stores anaccount 102 f including key information in place of the account 102 d.

A content distribution server 20 is included or annexed in/tobroadcast-side equipment 21. The broadcast-side equipment 21 is equippedwith an imaging device 220, a broadcast transmission unit 221, and atransmission antenna 222. In addition, a user information storage area206 is equipped with an account 206 d including key information in placeof the account 206 c shown in FIG. 1 .

A viewing device 35 in place of the viewing device 30 shown in FIG. 1 isequipped with a broadcast reception unit 320 and a reception antenna321, and a memory unit 302 stores an account 302 b including keyinformation. The communication unit 306 shown in FIG. 1 is not required.In addition, the broadcast-side equipment 21 and the viewing device 35communicate via a broadcasting satellite 60. In FIG. 6 , the samereference numeral is allocated to the same processing unit as that inthe embodiment shown in FIG. 1 and description of them is omitted.

In the broadcast-side equipment 21, the imaging device 220 is configuredby a camera, and the like and generates a real-time content program fora broadcast. After the broadcast transmission unit 221 converts acontent program for a broadcast from the imaging device 220 and acontent program from the content distribution server 20 to a videosignal and an audio signal, the broadcast transmission unit sequentiallyexecutes encode processing such as digital encoding and datacompression, multiplexing processing of (generating a transport stream(TS)) of video data and audio data, further, encryption processing ofthe transport stream (TS), error correcting code (Reed-Solomon Coding)adding processing and digital modulation processing, and the broadcasttransmission unit generate transmit information data. The broadcastinformation data generated by the broadcast transmission unit 221 issupplied to the transmission antenna 222.

The broadcast satellite 60 receives transmission information datatransmitted from the transmission antenna 222 as a radio wave andretransmits the transmission information data to the reception antenna321.

In the viewing device 35, the broadcast reception unit 320 sequentiallyapplies digital demodulation processing, error correcting processing,further, processing for decrypting and decoding the transport stream(TS), demultiplexing processing into video data and audio data anddecoding processing of each of video and audio respectively to a radiowave received via the reception antenna 321, and the broadcast receptionunit decodes the content program to a video signal and an audio signal.A display 305 displays the decoded video signal on its screen, a speaker309 reproduces the decoded audio signal as audio and a user can view thebroadcast content program.

As shown in FIG. 6 , as in the description of the embodiment shown inFIG. 1 , the mobile information terminal 11 acquires an account from thecontent distribution server 20. However, the mobile information terminal11 transmits broadcast content identification information 102 e showinga viewing-desired broadcast content program input and set to thebroadcast-side equipment 21 via an external network 50 and requestsissue of an account including key information required for decryptingthe broadcast content program the viewing of which is registered.

The transmission-side equipment 21 receives the account issue request,issues and stores the account 206 d including the key information, andtransmits the account to the mobile information terminal 11 via theexternal network 50. The mobile information terminal 11 transmits thereceived and stored account 102 f to the viewing-desired viewing device35 in the vicinity of the mobile information terminal 11 by short-rangewireless communication.

When a user closely holding the mobile information terminal 11 islocated in a range in which the user can view on the viewing device 35and the viewing device 35 receives the account 102 f from the mobileinformation terminal 11 by short-range wireless communication, theviewing device 35 stores the account 102 f received in the memory unit302 as an account 302 b. In addition, the broadcast reception unit 320in the viewing device 35 executes processing for decrypting and decodingthe encrypted and received transport stream (TS) by a broadcast usingthe key information received as the account 302 b, reproduces a videosignal and an audio signal, and enables viewing the rentedviewing-desired content program on the display 305 and via the speaker309.

In the abovementioned example, the key information received as theaccount 302 b is directly used for a scrambling key for decrypting thebroadcast content program in the form of the transport stream (TS).However, a method other than this may also be adopted. For example,related information acquired by encrypting key information required fordecrypting the content program is broadcast from the broadcast-sideequipment 21 separately from the broadcast content program, the relatedinformation is decrypted by the key information received as the account302 b, and the key information extracted as a result of decrypting therelated information may also be used for the scrambling key fordecrypting the broadcast content program.

Further, plural pieces of related information may also be provided, forexample, first and second related information are provided, the receivedfirst related information is decrypted by key information received asthe account 302 b, the second related information is decrypted by afirst key extracted as a result of decrypting the first relatedinformation, and the broadcast content program may also be decryptedusing a second key extracted as a result of decrypting the secondrelated information for a scrambling key. That is, the extraction ofeach key information piece for decryption and the decryption arerepeated for the broadcast plural pieces of related information and thebroadcast content program may also be decrypted using the finallyextracted key information for the scrambling key. In this case, securityfor protecting the content can be more enhanced by multiplexing ciphers.

Furthermore, in the abovementioned example, the case where the viewingcontracted content program is input and set is described. However, acase of a contract per channel (broadcast station) is also similar. Thatis, in this case, the user inputs and sets a viewing contracted channel(broadcast station) to be viewed on the viewing-desired viewing devicefrom the operation input unit 106 of the mobile information terminal 11after the user receives user authentication. The mobile informationterminal 11 has only to select broadcast-side equipment of acommunication destination according to the input/set viewing-desiredchannel (broadcast station), transmit broadcast channel identificationinformation showing the input/set viewing-desired broadcast channel tothe selected transmission-side equipment as the broadcast contentidentification information 102 e, and request issue of an accountincluding key information required for decrypting the viewing registeredbroadcast channel. Afterward, an encrypted and received transport stream(TS) is decrypted and decoded after similar processing to theabovementioned processing, a video signal and an audio signal arereproduced, and viewing of the renting/viewing-desired broadcast channelon the display 305 via the speaker 309 is enabled.

Owing to the abovementioned configuration, a user who already registersa viewable broadcast content program or a viewable broadcast channel(broadcasting station) by a paying contract, and the like beforehand canview the viewing-desired content program or the broadcast channel rentedvia a broadcast wave on any freely selected viewing device in thevicinity of the user anywhere using the mobile information terminal heldby the user, and user-friendly content viewing environment can beacquired. In the embodiment shown in FIG. 6 , the case of satellitebroadcasting using the broadcast satellite is described. However, it isevident that in a case of terrestrial digital broadcasting, the similaraction and effect are also acquired.

Next, an operational example of the content viewing system shown in FIG.6 will be described.

FIGS. 7A and 7B show one example of an operational sequence of thecontent viewing system shown in FIG. 6 . In FIG. 7 , as each unit whichis shown in FIGS. 2, 5 and to which the same reference numeral isallocated has the same operation as the operation already described inFIGS. 2, 5 , detailed description of the operation is omitted.

FIG. 7A basically shows substantially similar processing to theprocessing shown in FIG. 2A. However, for a hardware configuration, thecontent distribution server 20 shown in FIG. 2A is replaced with thebroadcast-side equipment 21, the mobile information terminal 10 isreplaced with the mobile information terminal 11, and the viewing device30 is replaced with the viewing device 35. In addition, for contents ofprocessing, the content program distributed via the network in FIG. 2Ais replaced with the broadcast content program distributed bybroadcasting in FIG. 7A. Except them, steps S201 to S206 in FIG. 7A aresimilar to those in FIG. 2A.

Afterward, the mobile information terminal 11 transmits the input andstored broadcast content identification information 102 e to the contentdistribution server 20 via a base station communication unit 103 and anexternal network 50 and requests issue of an account including keyinformation required for decrypting the broadcast content informationreceived on the viewing device 35 (S708).

After the content distribution server 20 receives the broadcast contentidentification information and the account issue request and verifiesthat viewing of the broadcast content program corresponding to thebroadcast content identification information is registered, it issues anaccount including the broadcast content identification information andthe key information and further, stores the issued account in a userinformation storage area 206 as an account 206 d (S709).

In addition, the content distribution server 20 transmits the issued andstored account 206 d to the mobile information terminal 11 via theexternal network 50 and a base station 40 (S710).

The mobile information terminal 11 stores the received account 206 d ina memory unit 102 as an account 102 f (S711 a). In the abovementionedaccount generation process, the content distribution server 20authenticates the user of the mobile information terminal 11 using theuser identification information and the user password respectively inputand set on the mobile information terminal 11, issues the accountincluding the key information for enabling decoding of the broadcastcontent program the viewing of which is set on the mobile informationterminal 11, and the mobile information terminal 11 can receive andstore the account transmitted from the content distribution server 20(S700 a).

Next, as shown in FIG. 7B, when the user closely holding the mobileinformation terminal 10 approaches the viewing-desired viewing device 35and further, performs simple one-touch input operation on the operationinput unit 106, the mobile information terminal 11 starts to transmitthe account 102 f via the short-range wireless communication unit 105 byshort-range wireless communication (S711 b). The transmitted account 102f is transmitted to the viewing device 35 existing in the vicinity ofthe mobile information terminal (S712).

The viewing device 35 periodically performs discrimination processing ofwhether the account 102 f transmitted from the mobile informationterminal by short-range wireless communication exists in a receivableclose range and can be received or whether the account 102 f existsoutside the receivable close range and cannot be received the account102 f at a fixed interval (S713).

When the viewing device 35 can receive the account 102 f, the viewingdevice 35 stores the received account 102 f in the memory unit 302 as anaccount 302 b (S714). In broadcasting the content program, thebroadcast-side equipment 21 generates and encrypts the content program,generates first related information (common information) acquired byuniting information related to control over the receiving viewing deviceand information of whether viewing is possible or not (for example, thisprogram is a sport program and is fee-based) and second relatedinformation (individual information) for decrypting the commoninformation (S715), and the broadcast-side equipment transmits them tothe viewing device 35 (S716).

The common information and the individual information are both encryptedand transmitted. Then, the broadcast reception unit 320 first decryptsthe individual information using the key information received from themobile information terminal 11, extracts a first key (a work key) fordecrypting the common information on the basis of the decoded individualinformation, next decrypts the common information using the first key(the work key), extracts a second key, and decrypts and decodes thebroadcast content program itself using the extracted second key for ascrambling key (S717).

Therefore, the user can view a video signal and an audio signal of thedecrypted and decoded broadcast content program on the display 305 viathe speaker 309 (S718) .

In addition, the viewing device discriminates whether the distributedcontent program is finished or not (S719), continues receivingdistribution when distribution of the content program to the viewingdevice is not finished, continues viewing of the content program (S720),terminates viewing of the program when the distribution of the contentprogram to the viewing device is finished (S721), and transmitsinformation showing that the viewed program is finished to the mobileinformation terminal 11 (S722).

The mobile information terminal 11 receives the termination of viewingthe content program, stops transmission of the account 102 f to theviewing device 35 (S723), and terminates content viewing on the viewingdevice by account renting. For timing of stopping transmitting theaccount 102 f from the mobile information terminal 11 to the viewingdevice 35, the present invention is not limited to the abovementionedtiming after viewing of the content program is finished and if onlytiming is after viewing is started on the viewing device 35, it needscarcely be said that the stop of transmission is possible at any timingtill an end of viewing. In this case, the mobile information terminal 11stops transmission of the account by transmitting information showingthe stop of the transmission of the account 102 f from the viewingdevice 35 to the mobile the content information terminal 11 afterviewing of program is started (S723).

According to the broadcast content viewing process by the abovementionedaccount transmission/reception, the viewing device periodically verifiesreception of the account from the mobile information terminal, decryptsand decodes the viewing-desired broadcast content program broadcast fromthe broadcast-side equipment using key information included in theaccount when the viewing device receives the account, and the viewing ofthe broadcast content program to the end is enabled (S700 b).

The case where the content program is rented and viewed in units ofprogram is described above. However, when a content is rented and viewedin units of channel (broadcast station), it is evident that the similaraction and effect are also acquired except viewing terminationprocessing if only a request for renting/viewing is made to a unit of achannel of contents in place of the unit of the broadcast contentprogram. That is, in the step S201, the unit of the content program hasonly to be replaced with the unit of the channel of contents, and in thesteps S707, S709, S715, S716, S717, the broadcast content program hasonly to be replaced with a broadcast channel.

As for the viewing termination processing, the case of renting/viewingin units of content program is described above in the abovementionedexample, processing for terminating renting/viewing is performed by theend of the content program. However, in a case of renting/viewing inunits of channel (broadcast station) of contents, renting/viewing can becontinued independent of an end of an individual program, and forexample, the processing for terminating renting/viewing has only to beperformed by separation of the mobile information terminal 11 from theviewing device 35 or by user’s input operation.

Consequently, when a user performs simple operation using the mobileinformation terminal held by the user, the user can view arenting/viewing-desired content program from a broadcast wave or abroadcast channel on the viewing device close to the user anywhere.

Example 4

Further, another embodiment in a case where a content program broadcastusing a radio wave and registered by a fee-based contract, and the likeis rented and viewed on a viewing device in the vicinity of a mobileinformation terminal will be described.

In this case, in satellite broadcasting generally widely used, broadcastreceiving is restrictively enabled only on a device into which a BSconditional access systems (B-CAS) (trademark) card is inserted byinserting the B-CAS card into a viewing device for viewing a broadcastcontent program, a video recorder for recording, and the like because ofcontent copyright protection and correspondence to accounting for paybroadcast including a case of terrestrial digital broadcasting (a B-CAScard system or a restrictive receiving system).

In a case of viewing a content program of pay broadcasting, control ismade so that only a user who contracts in a state in which informationin a B-CAS card and user identification information are linked can viewthe contracted content program on a viewing device into which the B-CAScard is inserted. The B-CAS card includes B-CAS card ID for identifyingthe B-CAS card, Entitlement Management Message (EMM) information(equivalent to the individual information) transmitted together with amaster key unique to this card and a broadcast wave, and the like, andthe EMM information includes contract information (a type and a term ofpay broadcasting) for every contracting user, a work key (equivalent tothe first key) for decrypting Entitlement Control Message (ECM)information (equivalent to the common information), and the like. TheECM information includes a scrambling key for encrypting the contentprogram, and the like.

For example, when a specific content program A of pay broadcasting iscontracted, the EMM information including the work key encryptedcorresponding to the broadcast content program A is transmitted to B-CAScard ID of a contracting user through an airwave and the EMM informationis rewritten. The work key of the broadcast content program A isdecrypted using the master key unique to the B-CAS card and isextracted. Next, the ECM information distributed together with theairwave is decrypted using the extracted work key of the broadcastcontent program A and a scrambling key is extracted. Further, video andaudio of the broadcast content program A distributed through the airwaveare decrypted using the extracted scrambling key so as to enable viewingthe broadcast content program A.

However, in this case, when the user contracting viewing of the contentprogram of pay broadcasting tries to view the contracted broadcastcontent program on another viewing device except a viewing device intowhich the linked B-CAS card is inserted, the B-CAS card is brought toanother viewing-desired viewing device and is required to be insertedinto it, and for the user who makes a fee-based contract, it is veryinconvenient.

FIG. 8 is a block diagram showing an embodiment of a content viewingsystem according to the embodiment for settling the abovementionedproblem. As shown in FIG. 8 , a viewing device 37 equipped with a B-CAScard 810 and a B-CAS card reader 811 and a viewing device 38 equippedwith a B-CAS card 812 and a B-CAS card reader 813 are provided inaddition to or in place of each configuration which is shown in FIG. 6and to which the same reference number is allocated. In FIG. 8 , thesame reference numeral is allocated to the same processing unit as eachprocessing unit in the embodiment shown in FIG. 6 and description ofthem is omitted.

The viewing device 37 having the similar configuration to that of theviewing device 35 reads/writes data from/to the B-CAS card 810 insertedinto the viewing device 37 by the B-CAS card reader 811. The viewingdevice 38 having the similar configuration to that of the viewing device35 reads/writes data from/to the B-CAS card 812 inserted into theviewing device 38 by the B-CAS card reader 813. As for the viewingdevice 37, viewing of the specific content program is already registeredby a user by the fee-based contract, and the like, in the B-CAS card810, B-CAS card ID linked with user identification information and themaster key unique to the B-CAS card are recorded, and in broadcast-sideequipment 21, the B-CAS card ID linked with the user identificationinformation and the master key unique to the B-CAS card are stored.

The user identification information is transmitted to the broadcast-sideequipment 21 from a mobile information terminal 11. The broadcast-sideequipment 21 authenticates the user and transmits the B-CAS card IDstored in a user information storage area 206 in a state linked with theuser identification information and a master key 206 e as an account tothe mobile information terminal 11 on the basis of a result of theauthentication. The mobile information terminal 11 transmits thereceived account 102 g to the viewing device 38 in the vicinity of themobile information terminal 11 via a short-range wireless communicationunit 105. The viewing device 38 decrypts and decodes the broadcastcontent program using B-CAS card ID and the master key respectivelyincluded in an account 302 c received via a short-range wirelesscommunication unit 304 in place of the B-CAS card ID and the master keyrespectively recorded in the B-CAS card 812 inserted into the viewingdevice 38.

Consequently, the user contracting viewing of the content program of paybroadcasting can view the contracted content program on anotherviewing-desired viewing device usably without inserting the B-CAS cardlinked with the user into the other viewing-desired viewing device bytransmitting information in the B-CAS card inserted into the viewingdevice linked with the user to the other viewing device for rentingusing the mobile information terminal. That is, the user can view theviewing-desired content program rented though the broadcast wave on theviewing device in the vicinity of the user anywhere using the mobileinformation terminal held by the user.

Next, an operational example of the content viewing system shown in FIG.8 will be described.

FIG. 9 show one example of an operational sequence of the contentdistribution system shown in FIG. 8 . In FIG. 9 , the same operation asthe operation already described in FIGS. 2, 5, 7 is allocated to eachsequence which is shown in FIGS. 2, 5, 7 and to which the same referencenumeral is allocated, and therefore detailed description of them isomitted.

In FIG. 9A, steps S201 to S707 are similar to the operational sequencedescribed referring to FIG. 7A. The mobile information terminal 11 thatreceives a result of authentication transmits input and setviewing-desired broadcast content identification information andrequests issue of an account as a result of authenticatingrenting/viewing of the broadcast content program from the viewing deviceA to the viewing device B (S908).

The content distribution server 20 extracts the B-into the CAS card IDof the B-CAS card 810 inserted viewing device 37 and linked with theuser identification information and the master key 206 e from the userinformation storage area 206 on the basis of a user authenticationresult, issues and stores an account having the extracted B-CAS card IDand the extracted master key (S909), and transmits the account to themobile information terminal 11 (S910).

The mobile information terminal 11 stores the received account in amemory unit 102 as an account 102 g (S911 a). According to theabovementioned account generation process, after user authentication,the B-CAS card ID of the viewing device 37 linked with the user, themaster key and the viewing-desired broadcast content identificationinformation can be stored in the mobile information terminal as theaccount (S900 a).

Next, as shown in FIG. 9B, when the user closely holding the mobileinformation terminal 11 approaches the viewing-desired viewing device 38and further, performs simple one-touch input operation on an operationinput unit 106, the mobile information terminal 11 starts transmittingthe account 102 g by short-range wireless communication via theshort-range wireless communication unit 105 (S911 b). The transmittedaccount 102 g is transmitted to the viewing device 38 in the vicinity ofthe mobile information terminal 11 (S912).

The viewing device 38 periodically executes discrimination processing ofwhether the account 102 g transmitted from the mobile informationterminal 11 by short-range wireless communication exists in a receivableclose range and can be received or the account 102 g is outside thereceivable close range and cannot be received at a certain fixedinterval (S913).

When the viewing device 38 can receive the account 102 g, the viewingdevice 38 stores the received account 102 g in a memory unit 302 as anaccount 302 c (S914) and extracts a master key stored as the account 302c (S915). That is, a broadcast reception unit 320 in the viewing device38 decrypts the broadcast content program using the master key of theviewing device 37 stored in the viewing device 38 as the account 302 cin place of the master key in the B-CAS card to be inserted into theviewing device 38.

In broadcasting the content program, the broadcast-side equipment 21generates and encrypts the broadcast content program, ECM informationand EMM information (S916), and when the contracted viewing-desiredbroadcast content program is broadcast via a broadcast satellite 60, theEMM information including the encrypted work key of the viewing-desiredcontent program is transmitted to B-CAS card ID stored in the viewingdevice 38 as the account 302 c through the airwave, and the EMMinformation is rewritten (S917). The received EMM information isdecrypted using the master key unique to the B-CAS car, and the EMMinformation is rewritten (S817). The received EMM information isdecrypted using the master key unique to the B-CAS card and the work keyof the content program is extracted (S918).

Next, the ECM information is distributed together with the airwave(S919), the ECM information is decrypted using the work key, and ascrambling key is extracted (S920). The viewing-desired broadcastcontent program is encrypted and is broadcast toward the viewing device38 (S921), and video and audio of the viewing-desired broadcast contentprogram are decrypted and decoded using the extracted scrambling key(S922). Therefore, the user can view a video signal and an audio signalof the decrypted and decoded broadcast content program on a display 305via a speaker 309 (S718) as described referring to FIG. 7 .

In addition, it is discriminated whether the distributed content programis finished or not (S719), when distribution of the content program tothe viewing device is not finished, the distribution is continued andviewing of the content program is continued (S720), when thedistribution of the content program to the viewing device is finished,the viewing of the program is finished (S721), and information showingan end of the viewing of the program is transmitted to the mobileinformation terminal 11 from the viewing device 38 (S722). The mobileinformation terminal 11 receives the end of the viewing of the contentprogram, stops transmitting the account 102 g to the viewing device 38(S723), and terminates the viewing of the content on the viewing deviceby renting the account.

It goes without saying that, for timing for stopping transmission of theaccount 102 g from the mobile information terminal 11 to the viewingdevice 38, the timing is not required to be after the abovementioned endof the viewing of the content program and if only the timing is afterthe viewing on the viewing device 38 is started, the timing may be atany timing till the end of the viewing. In this case, the mobileinformation terminal 11 can stop the transmission of the account bytransmitting information showing the stop of the transmission of theaccount 102 g from the viewing device 38 to the mobile informationterminal 11 after the viewing of the content program is started (S723).

According to the abovementioned broadcast content viewing process by thetransmission/reception of the account, the mobile information terminaltransmits/receives the account, the user rents information of the B-CAScard inserted into the registered viewing device 37 to the viewingdevice 38, and the broadcast content program can be viewed on theviewing device 38 (S900 b).

As described referring to FIG. 7 , in the abovementioned example, thecase where the content program is rented and viewed in units of programis described. However, it is evident that the similar action and effectare also acquired if only a request for renting/viewing is replaced witha unit of a channel of contents in place of the unit of the contentprogram except for viewing termination processing in a case ofrenting/viewing in units of channel (broadcast station) of contents. Inaddition, in the case of renting/viewing in units of channel (broadcaststation) of contents, processing for terminating renting/viewing hasonly to be performed by separating the mobile information terminal 11from the viewing device 38 or by user input operation for examplebecause renting/viewing are enabled regardless of an end of anindividual program.

Consequently, there is produced an effect that the user can view therenting/viewing-desired content program or the broadcast channel throughthe airwave on the viewing device close to the user by simple one-touchoperation using the mobile information terminal held by the user withoutbringing and installing the B-CAS card.

In addition, for a method of protecting copyright of contents of adigital broadcast, except the abovementioned method of using thephysical B-CAS card, a method of controlling by software withoutdepending the B-CAS card (a content protection method) is also used in aviewing device such as a tablet and a smartphone respectively equippedwith a television viewing function. As in the case of the B-CAS cardmethod, the content protection method is also operated on the basis ofthe transmission through a broadcast of the ECM information and the EMMinformation and the decryption of the content program by the master key,the work key and the scrambling key, and it need scarcely be said thatthe similar operation, action and effect can be realized by theoperational sequence example shown in FIG. 9 .

In the abovementioned embodiments, it is detected and recognized byshort-range wireless communication that the mobile information terminalheld by the user approaches the viewing device. However, the mobileinformation terminal and the viewing device are respectively equippedwith a global positioning system (GPS) receiving unit and bothapproaches may also be detected and recognized using each positionalinformation piece detected by each GPS receiving unit. For example,positional information detected by the GPS receiving unit of the mobileinformation terminal may be transmitted to the viewing device byshort-range wireless communication, the viewing device may collate thereceived positional information of the mobile information terminal andpositional information detected by the GPS receiving unit of the viewingdevice, and the viewing device may discriminate that the mobileinformation terminal and the viewing device are located close and theuser is located in a range in which the user can view the contentprogram on the viewing device.

The content distribution system and the content viewing system thatrespectively provide user-friendly viewing environment are provided byusing the technique described in the abovementioned embodiments when theuser holding the mobile information terminal rents and views the contentprogram or the broadcast channel respectively registered beforehand onthe viewing device in the vicinity of the user.

In addition, effectiveness of protecting contents can be enhancedfurther by limiting renting and distribution of the content program tothe viewing device that receives the account from the contentdistribution server to the unit of the program, for example, only oneprogram including the abovementioned case of relay viewing in theabovementioned embodiments of the content distribution system.

In the abovementioned embodiments of the content viewing system, theeffectiveness of protecting contents can be enhanced by limiting rentingand viewing of the broadcast content program to/on the viewing devicethat receives a broadcast wave to only the viewing device that receivesthe account and the unit of the program (only one program).

Further, in the content distribution server and the broadcast-sideequipment, the effectiveness of protecting contents can be enhanced byperforming accounting processing in units of rented content program forcompensation for distribution and viewing of the content program inissuing the account.

The present invention is not limited to the abovementioned embodimentsand various variations are included. For example, the abovementionedembodiments are detailedly described to clarify the present inventionand the present invention is not necessarily limited to theabovementioned all configurations. In addition, a part of theconfiguration in one embodiment can be replaced with the configurationin another embodiment and moreover, the configuration in anotherembodiment can also be added to the configuration in one embodiment.Further, the configuration in another embodiment can be added, deletedand replaced to/from/with a part of the configuration in eachembodiment.

Furthermore, a part or the whole of the abovementioned eachconfiguration, each function, each processing unit, each processingmeans, and the like may also be realized by hardware such as designingby an integrated circuit. Furthermore, the abovementioned eachconfiguration, each function, and the like may also be realized bysoftware by interpreting and executing a program for making a processorrealize respective functions. Information for realizing each functionsuch as a program, a table and a file can be stored in a recordingdevice such as a memory, a hard disk and a solid state drive (SSD) or ona record medium such as an IC card, an SD card and DVD.

Furthermore, as for a control line and an information line, only thoserequired for explanation are shown, and all control lines and allinformation lines in the product are not necessarily shown. Actually, itis considered that substantially all configurations are mutuallyconnected.

INDUSTRIAL APPLICABILITY

The present invention can be utilized for a content distribution systemfor distributing contents to a viewing device connected to a network anda content viewing system for viewing contents on a viewing device thatreceives a broadcast wave.

REFERENCE SIGNS LIST

10, 11: Mobile information terminal, 20: Content distribution server,21: Transmission-side equipment, 30, 31, 32, 35, 37, 38: Viewing device,40: Base station, 50: External network, 60: Broadcast satellite, 100,200, 300: Bus, 101, 201, 301: Control unit, 102, 202, 302: Memory unit,103: Base station communication unit, 104: Audio input-output processingunit, 105: Short-range wireless communication unit, 106, 307: Operationinput unit, 107, 305: Display, 203, 306: Communication unit, 204:Storage, 205: Content information storage area, 206: User informationstorage area, 303: Storage unit, 309: Speaker, 220: Imaging device, 221:Broadcast transmission unit, 222: Transmission antenna, 320: Broadcastreception unit, 321: Reception antenna, 810, 812: B-CAS card, 811, 813:B-CAS card reader

1. A content viewing method using a viewing system including a contentdistribution server that distributes contents, a mobile informationterminal, and a viewing device that reproduces a content, comprising: afirst step in which the mobile information terminal transmits useridentification information and a user password to the contentdistribution server; a second step in which the content distributionserver authenticates the mobile information terminal on the basis of thereceived user identification information and the received user password;a third step in which the mobile information terminal transmits anaccount issue request for requesting an account for reproducing adesired content to the content distribution server; a fourth step inwhich the content distribution server issues the account on the basis ofthe received account issue request and transmits the issued account tothe mobile information terminal; a fifth step in which the mobileinformation terminal stores the received account; a sixth step in whichthe mobile information terminal transmits the stored account byshort-range wireless communication; a seventh step in which the viewingdevice stores the account received by the short-range wirelesscommunication; and an eighth step in which the viewing device reproducesthe desired content using the stored account.
 2. The content viewingmethod according to claim 1, wherein the content distribution server,the mobile information terminal, and the viewing device are connectedvia a network; and in the eighth step, the viewing device transmits theaccount to the content distribution server via the network so as torequest viewing, receives the desired content transmitted by the contentdistribution server according to the viewing request, and reproduces thedesired content.
 3. The content viewing method according to claim 2,wherein in the sixth step, the mobile information terminal continuouslytransmits the stored account by short-range wireless communication; andthe viewing device executes a ninth step in which the viewing devicetransmits a viewing halt request to the content distribution server viathe network when the reception of the account continuously transmittedis interrupted during execution of the eighth step and the viewingdevice interrupts reproduction of the desired content when the contentdistribution server halts transmission of the desired content accordingto the viewing halt request.
 4. The content viewing method according toclaim 3, wherein the viewing device executes a tenth step in which theviewing device transmits the account to the content distribution servervia the network so as to request viewing when reception of the accountis resumed after the reception of the continuously transmitted accountis interrupted and the ninth step is executed, receives the desiredcontent transmitted by the content distribution server according to theviewing request, and resumes the interrupted reproduction of the desiredcontent.
 5. The content viewing method according to claim 3, furthercomprising, after the viewing device executes the ninth step using asecond viewing device apart from the viewing device: an eleventh step inwhich the mobile information terminal transmits the stored account byshort-range wireless communication; a twelfth step in which the secondviewing device stores the account received by short-range wirelesscommunication and a thirteenth step in which the second viewing devicetransmits the account to the content distribution server via the networkso as to request viewing, receives the desired content transmitted bythe content distribution server according to the viewing request, andresumes interrupted reproduction of the desired content.
 6. The contentviewing method according to claim 5, wherein in the ninth step, further,the viewing device transmits viewing interruption information showing aviewing interrupted position or viewing interrupted time of the desiredcontent to the mobile information terminal when reception of thecontinuously transmitted account is interrupted and the mobileinformation terminal stores the viewing interruption information; in theeleventh step, further, the mobile information terminal transmits thestored viewing interruption information to the second viewing device bythe short-range wireless communication; and in the thirteenth step,further, the second viewing device resumes the interrupted reproductionof the desired content from the viewing interrupted position or theviewing interrupted time on the basis of the received viewinginterruption information.
 7. The content viewing method according toclaim 3, wherein the mobile information terminal starts or haltstransmitting the stored account by the short-range wirelesscommunication according to operation of a user.
 8. The content viewingmethod according to claim 1, wherein the content distribution server andthe mobile information terminal are connected via a network; the contentis encrypted and is wirelessly broadcast from the content distributionserver to the viewing device; the account includes key information fordecrypting the wirelessly broadcast content; and in the eighth step, theviewing device receives the desired content wirelessly broadcast fromthe content distribution server, decrypts the desired content using thekey information, and reproduces the desired content.
 9. The contentviewing method according to claim 8, the eighth step, the viewing devicewherein in the eighth step, the viewing device receives encryptedrelated information including a scrambling key for decrypting thedesired content from the content distribution server, decrypts therelated information by the key information, decrypts the desired contentusing the scrambling key extracted by decrypting the relatedinformation, and reproduces the desired content.
 10. The content viewingmethod according to claim 9, wherein the related information isconfigured by encrypted first and second related informationrespectively including first and second keys respectively required fordecrypting the desired content; and the viewing device decrypts thefirst related information by the key information, decrypts the secondrelated information using the first key extracted by decrypting thefirst related information, decrypts the content key extracted by desiredusing the second decrypting the second related information, andreproduces the desired content.
 11. The content viewing method accordingto claim 1, wherein the content distribution server and the mobileinformation terminal are connected via a network; the content isencrypted and is wirelessly broadcast from the content distributionserver to the viewing device used for a second viewing device and afirst viewing. device different from the viewing device; a wirelessbroadcast transmits encrypted first related information including afirst key required for decrypting the content and encrypted secondrelated information including a second key together with the content;the first viewing device and the second viewing device can utilize afirst device and a second device installed in each viewing device; thefirst device stores first ID linked with the user identificationinformation and a first master key unique to the first device; thecontent distribution server stores the first ID and the first master keybeforehand; in the fourth step, the content distribution server issuesthe first ID and the first master key on the basis of the receivedaccount issue request as an account and transmits the issued account tothe mobile information terminal; in the fifth step, the mobileinformation terminal stores the first ID and the first master key as theaccount; in the sixth step, the mobile information terminal transmitsthe first ID and the first master key by short-range wirelesscommunication as the account; in the seventh step, the second viewingdevice stores the first ID and the first master key as the account; andin the eighth step, the second viewing device decrypts the first relatedinformation by the first master key included in the account, decryptsthe second related information using the first key extracted bydecrypting the first related information, decrypts the content using thesecond key extracted by decrypting the second related information, andenables reproduction of the content.
 12. A mobile information terminalused for a content viewing method using a viewing system including acontent distribution server that distributes contents, the mobileinformation terminal, and a viewing device that reproduces a content,comprising: a control unit; a memory unit; a first communication unitfor communicating with the content distribution server; a secondcommunication unit having shorter communication distance than the firstcommunication unit for communicating with the viewing device; and aninput unit, wherein the memory unit stores user identificationinformation and a user password; the control unit instructs the firstcommunication unit to transmit the user identification information andthe user password to the content distribution server; the control unitinstructs the first communication unit to transmit an account issuerequest for requesting an account for reproducing a desired content tothe content distribution server; the control unit instructs the firstcommunication unit to store the account received from the contentdistribution server in the memory unit; and unit instructs the secondcommunication the control unit to continuously or periodically transmitthe account.
 13. The mobile information terminal according to claim 12,of start, continuation, wherein at least one interruption and resumptionof continuous or periodic transmission of the account by the secondcommunication unit is enabled by operation of a user via the input unit.14. The mobile information terminal according to claim 12, wherein thecontrol unit instructs the second communication unit to store viewinginterruption information showing a viewing interrupted position orviewing interrupted time of the desired content in the memory unit whenthe second communication unit receives the viewing interruptioninformation from the viewing device.
 15. The mobile information terminalaccording to claim 12, wherein a content distributed from the contentdistribution server is broadcast on a first viewing device and a secondviewing device via broadcast-side equipment after the content isencrypted, and the first viewing device and the second viewing devicedecode the content using first key information and second keyinformation respectively stored; the control unit instructs the firstcommunication unit to receive the same information as the first keyinformation stored in the first viewing device from the contentdistribution server via the first control unit and to store theinformation in the memory unit as an account; and the control unitinstructs the second communication unit to transmit the first keyinformation to the second viewing device by continuously or periodicallytransmitting the account.